Prior art balers of this type generally have a bale forming chamber defined by an apron comprising an array of side-by-side belts, transverse slats extending between chains, a plurality of bale forming rolls or a combination of these various elements, e.g., bale forming rolls and side-by-side belts. The utilization of rolls in combination with belts is shown by way of example in the round baler of U.S. Pat. No. 5,044,272 issued Sep. 3, 1991 to Richard E. Jennings.
During field operation, a pickup assembly picks up crop material, such as hay, from the ground and feeds it into a fixed or adjustable chamber where it is rolled up to form a compact cylindrical package of hay. While still inside the bale forming chamber the formed package is wrapped in its compacted form by net, twine or the like, prior to being ejected as a bale from the baler onto the ground for subsequent handling.
Round balers of the various configurations mentioned above commonly have a pickup that feeds crop material along a path by means of tines that engage a windrow of crop material on the ground. Other feed assist means such as fingers may be used along the path to urge the material along. Pickup assemblies have encountered problems of varying degree caused by stray crop material and other debris, such as dirt, crop juices and dust, in the bearing assemblies for the rotatable transverse shafts. When the crop material being baled is damp, and particularly if it is a short cut of grass crop, the fine random debris being agitated as it is being picked up and formed into a cylindrical package also gives cause for concern. Field experience has shown that costly bearing seals are necessary to prevent such unwanted debris from working its way into the pickup assembly bearing cavities. If permitted to go uncorrected, serious wear problems could occur culminating in bearing failure.
A known attempt in the prior art to reduce or overcome this problem has been successful but costly. This arrangement, shown in FIG. 1 of the drawings, is described in detail hereinbelow.
In any attempted solution, maintaining the integrity of the bearing cavity for long and continuous use in the field environment described above is a key design criteria. As mentioned above, if debris is permitted to enter the bearing cavity it will cause an unwanted affect on operation of the bearing assembly and ultimate failure of the pickup, resulting in machine downtime.
Although known prior art arrangements for preventing debris from entering the bearing cavity of shaft mounting assemblies have met with varying degrees of success, the root of the problem continues to be derived from the environment in which the invention is used unwanted debris continually exists, especially during long periods of operation of the pickup. When this debris works past the known shielding devices and ultimately penetrates the bearing seal it will cause bearing failure if uncorrected. Thus, integrity of the debris shield over long periods of use is an important aspect of reliable round baler performance to which the present invention is devoted.